March, i&j6 ] FoX, Nol-ITII AMERICAN SpECIES OF NySSOX. 15 



15. Nysson rufiventris Cress. 



Nyssoti rufiventris Cresson, ibid, p. 283, 9 • 



Montana; Colorado. 



16. Nysson fidelis Cress. 



Xysson fidelis Cresson, ibid, p. 282, J $ . 



Montana ; Colorado. 



17. Nysson simplicicornis, sp. nov. 



^ — Cheel;s not margined posteriorly beneath, rather finely punctured; front 

 with distinct, somewhat separated and strong, punctures, slightly prominent above the 

 antenna ; between ocelli flat, not tuberculate ; clypeus transversely depressed before 

 apical margin, which is subtruncate ; antennae slenderer than in the allied species 

 scape shining, punctured, flagellum opaque, the apical joint not curved or enlarged, 

 obtuse at tip, the preceding joint not at all produced at apex beneath ; dorsulum with 

 coarse shallow punctures, or rugoso-punctate ; scutellum coarsely punctured, not 

 margined laterally ; mesopleuras coarsely punctured but less so than the dorsulum ; 

 middle segment with the spines sharp, slender, enclosure irregularly ridged; hind 

 tibi;^ not spinose ; wings sub-hyaline, nervures and stigma black, petiole of second 

 submarginal cell shorter than the height of cell, submedian cell of posterior wings 

 terminating at the origin of the cubital vein, punctures of the abdomen distinct, finer 

 and closer, however, than in lateralis, second ventral segment strongly convex, with 

 the punctures sparser, last dorsal bidentate. Black ; spot at apex of four anterior 

 femora beneath and on dorsal segments 1-3, whitish; mandibles reddish medially ; 

 tarsi somewhat testaceous ; clypeus and sides of face with dense silvery pubescence. 

 Length 5 mm. 



Ingham County, Michigan (G. C. Davis), July 17th. Smaller 

 than the allied species with black abdomens and is at once separated 

 by the different terminal antennal joint. 



1 8. Nysson opulentus Gerst. 



Nysson opulentus Gerstacker, Abh. Naturh. Gesell. zu Halle, X, p. 1 14, $ 

 Nysson opulentus Cresson, Tr. Am. Ent. Soc. IX, p. 279, 9. 

 N'ysson opulentus Handlirsch, 1. c. p. 357, 9 <?• 



New York. The $ I have not seen. 



19. Nysson mellipes Cress. 



Nysson mellipes Cressun, Am. Ent. Soc. IX, p. 279, $ 9. 

 Colorado ; Dakota ; Montana. 



20. Nysson tuberculatus Hdl. 



Nysson tuberculatus Haxdlirsch, I. c. p. 363, $ 9 ■ 



Wisconsin and South Carolina (Handlirsch). Unknown to me. 

 It is said to be close to basilaris, but seems to differ somewhat in the 

 punctuation of abdomen, greater extent of black on legs and presence 



